Analysis of Gene Recombination between HLA-B and -DRB1, HLA-DQB1 and -DPB1 Loci / 中国实验血液学杂志

OBJECTIVE@#To investigate the recombinations within the human leukocyte antigen (HLA) region in two families.@*METHODS@#Genomic DNA was extracted from the peripheral blood specimens of the different family members. HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1 loci were genotyped using polymerase chain reaction-sequence specific oligonucleotide probing technique (PCR-SSO) and next-generation sequencing technique. HLA haplotype was determined by genetic analysis of the pedigree.@*RESULTS@#The haplotypes of HLA-A*11:01~C*03:04~B*13:01~DRB1*12:02~DQB1*03:01~DPB1*05:01:01G and HLA-A*03:01~C*04:01~B*35:03~DRB1*12:01~DQB1*03:01~DPB1*04:01:01G in the family 1 were recombined between HLA-B and HLA-DRB1 loci, which formed the haplotype of HLA-A*11:01~C*03:04~B*13:01~DRB1* 12:01~DQB1*03:01~DPB1*04:01:01G. The haplotypes of HLA-A *02:06~C*03:03~B*35:01~DRB1*08:02~DQB1*04:02~ DPB1*13:01:01G and HLA-A *11:01~C*07:02~B*38:02~DRB1*15:02~DQB1*05:01~DPB1*05:01:01G in the family 2 were recombined between HLA-DQB1 and HLA-DPB1 loci, which formed the haplotype of HLA-A*02:06~C*03:03~B*35:01~ DRB1*08:02~DQB1*04:02~DPB1*05:01:01G.@*CONCLUSION@#The gene recombination events between HLA-B and -DRB1, HLA-DQB1 and -DPB1 loci were found respectively in two Chinese Han families.

Identification of a novel HLA-DQB1*03 allele caused by variant of a single nucleotide / 中华医学遗传学杂志

OBJECTIVE@#To delineate the characteristics of a novel HLA-DQB1 allele identified during routine HLA matching in a leukemia family.@*METHODS@#The mother and brother of the patient were subjected to PCR sequence-specific oligonucleotide probe (SSOP), PCR sequence-based typ1ing (SBT), as well as next-generation sequencing (NGS).@*RESULTS@#PCR-SBT revealed that the patient's mother and brother's HLA-DQB1 sequences did not fully match with any known allele combination. NGS revealed that the novel allele has differed from the closest matched DQB1*03:02 with a T>G substitution at position 233 in exon 2, which resulted in substitution of Valine at codon 46 by Glycine. Pedigree analysis confirmed that the novel HLA-DQB1 allele was inherited from his mother.@*CONCLUSION@#A novel HLA-DQB1 allele has been identified through next generation sequencing and was officially named as HLA-DQB1*03:362 by the World Health Organization HLA Factor Nomenclature Committee.

Search for DQ2 5 and DQ8 alleles using a lower cost technique in patients with type 1 diabetes and celiac disease in a population of southern Brazil

ABSTRACT Objective To evaluate the frequency of DQ2.5 and DQ8 alleles using the Tag-single-nucleotide polymorphism (Tag-SNP) technique in individuals with type 1 diabetes mellitus (T1DM) and celiac disease (CD) in southern Brazil. Materials and methods In a prospective design, we performed the search for DQA1*0501 and DQB1*0201 alleles for DQ2.5 and DQB1*0302 for DQ8 through Real-Time Polymerase Chain Reaction (RT-PCR) technique, using TaqMan Genotyping Assays (Applied Biosystems, USA). The diagnosis of CD was established by duodenal biopsy and genotypic determination performed by StepOne Software v2.3. Allelic and genotypic frequencies were compared between groups using Chi-square and Fisher's exact tests and the multiple comparisons using Finner's adjustment. Results Three hundred and sixty two patients with a median age of 14 years were divided into 3 groups: T1DM without CD (264); T1DM with CD (32) and CD without T1DM (66). In 97% of individuals with T1DM and CD and 76% of individuals with CD without T1DM, respectively, the alleles DQ2.5 and/or DQ8 were identified (p < 0.001). DQ2.5 was more common in individuals with CD (p = 0.004) and DQ8 was more common in individuals with type 1 diabetes (p = 0.008). Conclusions The evaluation of the alleles for DQ2.5 and DQ8 by Tag-SNP technique showed a high negative predictive value among those with T1DM, similar to that described by the conventional technique. The high frequency of DQ8 alleles in individuals with T1DM did not allow differentiating those at higher risk of developing T1DM.

Is there a relationship between narcolepsy, multiple sclerosis and HLA-DQB1* 06: 02? / Existe relação entre narcolepsia, esclerose múltipla e HLA-DQB1* 06: 02?

ABSTRACT We studied multiple sclerosis (MS) patients with the HLA-DQB1*06:02 allele and compared them with MS patients who did not carry the HLA-DQB1*06:02 allele. We analyzed clinical and neurophysiological criteria for narcolepsy in six MS patients with HLA-DQB1*06:02, compared with 12 MS patients who were HLA-DQB1*06:02 non-carriers. Only two patients with HLA-DQB1*06:02 allele scored higher than 10 on the Epworth Sleepiness Scale. Polysomnography recording parameters and the multiple sleep latency test showed an absence of narcolepsy in the study group. Our study suggested no significant correlation between narcolepsy, MS and HLA-DQB1*06:02. The HLA-DQB1*06:02 allele alone was not sufficient to cause MS patients to develop narcolepsy.

RESUMO Pacientes com esclerose múltipla (EM) portadores do alelo HLA-DQB1*06:02 foram estudados e comparados com pacientes com EM mas que não são portadores do alelo HLA-DQB1*06:02. Os critérios clínicos e neurofisiológicos para narcolepsia foram analisados em pacientes com EM sendo 6 pacientes com o HLA-DQB1*06:02 comparados a 12 pacientes sem o HLA-DQB1*06:02. Somente 2 pacientes com EM e HLA-DQB1*06:02 tiveram escore maior que 10 na escala “Epworth Sleepiness Scale”. Os parâmetros da polissonografia e o teste de múltiplas latências do sono mostraram ausência de narcolepsia no grupo estudo. Nosso estudo não sugere correlações significantes entre narcolepsia, EM e HLA-DQB1*06:02. Somente o HLA-DQB1*06:02 não foi suficiente para desenvolver narcolepsia em pacientes com EM.

Impact of Light Salt Substitution for Regular Salt on Blood Pressure of Hypertensive Patients / Impacto da Substituição de Sal Comum por Sal Light sobre a Pressão Arterial de Pacientes Hipertensos

Background: Studies have shown sodium restriction to have a beneficial effect on blood pressure (BP) of hypertensive patients. Objective: To evaluate the impact of light salt substitution for regular salt on BP of hypertensive patients. Methods: Uncontrolled hypertensive patients of both sexes, 20 to 65 years-old, on stable doses of antihypertensive drugs were randomized into Intervention Group (IG - receiving light salt) and Control Group (CG - receiving regular salt). Systolic BP (SBP) and diastolic BP (DBP) were analyzed by using casual BP measurements and Home Blood Pressure Monitoring (HBPM), and sodium and potassium excretion was assessed on 24-hour urine samples. The patients received 3 g of salt for daily consumption for 4 weeks. Results: The study evaluated 35 patients (65.7% women), 19 allocated to the IG and 16 to the CG. The mean age was 55.5 ± 7.4 years. Most participants had completed the Brazilian middle school (up to the 8th grade; n = 28; 80.0%), had a family income of up to US$ 600 (n = 17; 48.6%) and practiced regular physical activity (n = 19; 54.3%). Two patients (5.7%) were smokers and 40.0% consumed alcohol regularly (n = 14). The IG showed a significant reduction in both SBP and DBP on the casual measurements and HBPM (p < 0.05) and in sodium excretion (p = 0.016). The CG showed a significant reduction only in casual SBP (p = 0.032). Conclusions: The light salt substitution for regular salt significantly reduced BP of hypertensive patients. .

Fundamento: Alguns estudos demostraram um efeito benéfico da restrição de sódio na pressão arterial (PA) de hipertensos. Objetivo: Avaliar o impacto da substituição do sal comum por sal light na PA de hipertensos. Métodos: Hipertensos não controlados, de ambos os sexos, com idades entre 20 e 65 anos, e usando doses estáveis de anti-hipertensivos foram randomizados para um Grupo Intervenção (GI - recebendo sal light) e um Grupo Controle (GC - recebendo sal comum). A PA sistólica (PAS) e a PA diastólica (PAD) foram analisadas usando-se medidas casuais da PA e Monitoração Residencial da Pressão Arterial (MRPA), e a excreção de sódio e potássio foi avaliada em amostras de urina de 24 horas. Os pacientes receberam 3 g de sal para consumo diário por 4 semanas. Resultados: Este estudo avaliou 35 pacientes (65,7% mulheres), 19 alocados no GI e 16 no GC. A idade média foi de 55,5 ± 7,4 anos. A maioria dos participantes havia completado o ensino fundamental (até a 8a série; n = 28; 80,0%), tinha renda familiar de até dois salários mínimos (n = 17; 48,6%) e praticava atividade física regularmente (n = 19; 54,3%). Dois pacientes (5,7%) eram fumantes e 40,0% consumiam álcool com regularidade (n = 14). O GI mostrou uma significativa redução tanto da PAS quanto da PAD nas medidas casuais e de MRPA (p < 0,05) e, ainda, diminuição da excreção de sódio (p = 0,016). O GC apresentou redução significativa apenas na medida casual da PAS (p = 0,032). Conclusões: A substituição do sal comum por sal light diminuiu significativamente a PA de hipertensos. .

Performance of LIFECODES HLA-DQB1 Typing Kit Using Luminex Platform in Koreans

Intermediate-resolution HLA-DQ typing has gained importance in organ transplantation recently. We evaluated the performance of the LIFECODES HLA-DQB1 typing kit (Immucor, USA) using sequence-specific oligonucleotide (SSO) probe and Luminex platform (Luminex Corp., USA) on 100 samples tested by sequence-based typing (SBT) using the AlleleSEQR HLA-DQB1 kit (Abbott Molecular, USA) in Korean individuals. No sample showed ambiguity in the assignment of 4-digit HLA-DQB1 allele with the LIFECODES HLA-DQB1 SSO typing kit, and the results were fully concordant with those of high-resolution typing of AlleleSEQR HLA-DQB1 SBT up to 4-digit level. Three samples required adjustment of false reactions (3/100, 3.0%): two samples with DQB1*03:03/*06:01 showed false-positive result in probe 253, and 1 sample with DQB1*04:02/*05:02 showed false-negative result in probe 217. We tested an additional sample with DQB1*03:03/*06:01, which showed same false-positivity in probe 253 and 2 samples with DQB1*04:02/*05:02, which showed no false reaction. The false reactions did not result in ambiguity or change in the HLA allele assignment. We could assign HLA-DQB1 alleles to 4 digit-level without ambiguity, with 100% concordance with the SBT results. Thus, LIFECODES HLA-DQB1 SSO typing kit showed good performance for intermediate-resolution HLA-DQB1 typing in clinical laboratory for organ transplantation in Koreans.

Association between HLA-DQB1[asterisk]03:01 and Bullous pemphigoid in Iranian patients

A common Human Leukocyte Antigen [HLA] class II allele, DQ beta 1[asterisk]03:01, seems to be associated with Bullous pemphigoid [BP] in Caucasians whereas previous studies in other ethnic groups showed other HLA class II alleles as genetic predisposing factors for BP. To investigate the association of HLA class II alleles and haplotypes with BP in Iranian population. Methods: Fifty patients with Bullous pemphigoid and 180 geographically matched, healthy individuals as control group enrolled into this study. HLA typing of class II [DR and DQ alleles] was carried out using polymerase chain reaction based on sequence-specific primers method. Class II DQA1 and DQB1 typing showed a significantly higher frequency of HLA-DQA1[asterisk]05:01 [45% vs. 33%, p=0.03], HLA-DQB1[asterisk]03:01 [36% vs. 23.6%, p=0.02] and HLA-DQB1[asterisk]04:01 [4% vs. 1.6%, p=0.04] in the BP patients compared with controls. For DRB1 allele frequencies, there were no significant disease associations. The frequency of DRB1[asterisk]08:01/DQA1[asterisk]05:01/DQB1[asterisk]03:01 [3% vs. 0%, p=0.02] haplotype showed an increase among patients compared with controls. Our data suggest that Iranian patients with BP present the same genetic predisposition linked to HLA-DQB1[asterisk]03:01 previously reported in Caucasians

Frecuencia de alelos HLA de clase I y II en una cohorte de pacientes con espondiloartritis provenientes del noroccidente colombiano / Frequency of HLA alleles class I and II in a cohort of northwestern Colombian patients with spondyloarthritis

Introducción. Las espondiloartritis son enfermedades reumatológicas crónicas que afectan el esqueleto axial y las articulaciones periféricas, con varias manifestaciones extraarticulares. La asociación con el HLA-B27 sigue siendo uno de los vínculos más fuertes conocidos entre estas entidades y el complejo mayor de histocompatibilidad; sin embargo, la distribución mundial del HLA-B27 varía considerablemente y se han descrito asociaciones con genes no HLA-B27. Objetivo. Conocer la frecuencia de alelos HLA de clase I y II en pacientes con espondiloartritis provenientes del noroccidente colombiano y su frecuencia en las manifestaciones clínicas y radiológicas específicas. Materiales y métodos. Se condujo un estudio descriptivo, observacional, de corte transversal, retrospectivo y prospectivo entre 2005 y 2008 de 56 pacientes colombianos con espondiloartritis. Se identificaron los alelos correspondientes a los loci HLA de clase I y II (HLA-B, HLADQB1 y HLADRB). Se analizó su frecuencia con las manifestaciones clínicas axiales, periféricas, extraarticulares y radiológicas. Resultados. Se encontró una baja frecuencia de HLA-B27 en la población total (50 %), aunque fue el alelo más frecuente, junto con HLA-DRB4*01 (35,7 %) y HLA-DQB1*0501 (28,6 %), en todos los pacientes en general y en cada una de las manifestaciones clínicas y radiológicas. Se resalta la alta frecuencia de HLA-B27 y HLA-DRB4*01 (64,3 %) en pacientes con dactilitis, hallazgo novedoso sin previa descripción. Conclusión. Los alelos HLA-B27, HLA-DRB4*01 y HLA-DQB1*0501 fueron frecuentes en los diferentes subtipos de espondiloartritis y en las manifestaciones clínicas axiales, periféricas y extraarticulares específicas, además de la sacroiliítis radiológica.

Introduction. Spondyloarthritis is a chronic rheumatic disease that affect the axial skeleton and peripheral joints, along with several extra-articular manifestations. The association with HLA-B27 remains one of the strongest known links between these entities and the major histocompatibility complex. However, the global distribution of HLA-B27 varies considerably and furthermore, associations with non-HLA-B27 genes have been described. Objective. The frequency of HLA class I and II was determined in a population of patients with spondyloarthritis with respect to detection in the clinical setting and by radiology. Materials and methods. A descriptive, observational, cross-sectional, retrospective and prospective study was conducted in 56 patients from northwestern Colombia. Each was diagnosed with spondyloarthritis between 2005 and 2008. In each case, alleles were identified for the loci HLA class I and II (HLA-B; HLADQB1 and HLADRB). The frequency of these alleles in the axial, peripheral, extraarticular and radiological manifestations. Results.The frequency of HLA-B27 was 50% overall, and it was the most frequent allele. The two other alleles were HLA.DRB4*01 at 35.7% and HLA-DQB1*0501 at 28.6%, as detected in each of the clinical and radiological manifestations. A high frequency of HLA-B27 and HLA-DRB4*01 (64.3%) was noted in patients with dactylitis. Conclusion. The alleles HLA-B27, HLA-DRB4*01 and HLA-DQB1*0501 were common in the different subtypes of spondyloarthritis and were frequent in the specific clinical axial, peripheral and extraarticular clinical manifestations, as well as radiological sacroiliitis.

Molecular analysis of human leukocyte antigen class I and class II allele frequencies and haplotype distribution in Pakistani population.

AIM: Distribution of HLA class I and II alleles and haplotype was studied in Pakistani population and compared with the data reported for Caucasoid, Africans, Orientals and Arab populations. MATERIALS AND METHODS: HLA class I and II polymorphisms in 1000 unrelated Pakistani individuals was studied using sequence-specific primers and polymerase chain reaction and assay. RESULTS: The most frequent class I alleles observed were A*02, B*35 and CW*07, with frequencies of 19.2, 13.7 and 20%, respectively. Fifteen distinct HLA-DRB1 alleles and eight HLA-DQB1 alleles were recognized. The most frequently observed DRB1 alleles which represented more than 60% of the subjects were DRB1 *03, *07, *11 and *15. The rare DRB1 alleles detected in this study were HLADRB1 *08 and *09, having frequencies of 0.9 and 1.7%, respectively. In addition, at DRB1-DQB1 loci there were 179 different haplotypes and 285 unique genotypes and the most common haplotype was DRB1*15-DQB1*06 which represented 17% of the total DRB1-DQB1 haplotypes. In our population, haplotype A*33-B*58-Cw*03 comprised 2.8% of the total class I haplotypes observed. This haplotype was seen only in the oriental populations and has not been reported in the African or European Caucasoid. CONCLUSION: Our study showed a close similarity of HLA class I and II alleles with that of European Caucasoid and Orientals. In Pakistani population, two rare loci and three haplotypes were identified, whereas haplotypes characteristic of Caucasians, Africans and Orientals were also found, suggesting an admixture of different races due to migration to and from this region.